Windows 7 Upgrade Advisor tool failed to run with the error message “Windows 7 Upgrade Advisor was unable to reach the Microsoft server for compatibility information. Check your Internet connection and try again later.”
SYMPTOM
When you run the Windows 7 Upgrade Advisor tool on a system which use a proxy to access the Internet you receive the error:
“Windows 7 Upgrade Advisor was unable to reach the Microsoft server for compatibility information. Check your internet connection and try again later.”
In the error log (%temp%\WuaDiagnostics.log) you can see the update advisor tries to access:
https://aeos.microsoft.com/compatibilityexchange/compatibilityexchange.svc and then receives the error like following:
[7/23/2010 12:04:41 PM] Exception: The request failed with HTTP status 407: Proxy Authentication Required
ROOT CAUSE
The Windows 7 Upgrade Advisor does not support proxy authentication.
RESOLUTION
On the proxy server, creating an anonymous access rule specific to the destinations FQDN's used by the Windows 7 Upgrade Advisor. For example, you may create the following rules:
Action: Allow
Protocols: HTTP, HTTPS
From/Listener: Internal
To: Domain Name Set
aeos.microsoft.com
aestats.microsoft.com
crl.microsoft.com
download.microsoft.com
go.microsoft.com
Condition: All Users
REFERENCES
https://social.answers.microsoft.com/Forums/en/w7install/thread/5522421e-b7f7-4508-b785-90aeb76dd864